Once we have sequenced genomes in the previous course, we would like to compare them to determine how species have evolved and what makes them different.
In the first half of the course, we will compare two short biological sequences, such as genes (i.e., short sequences of DNA) or proteins. We will encounter a powerful algorithmic tool called dynamic programming that will help us determine the number of mutations that have separated the two genes/proteins.
In the second half of the course, we will "zoom out" to compare entire genomes, where we see large scale mutations called genome rearrangements, seismic events that have heaved around large blocks of DNA over millions of years of evolution. Looking at the human and mouse genomes, we will ask ourselves: just as earthquakes are much more likely to occur along fault lines, are there locations in our genome that are "fragile" and more susceptible to be broken as part of genome rearrangements? We will see how combinatorial algorithms will help us answer this question.
Finally, you will learn how to apply popular bioinformatics software tools to solve problems in sequence alignment, including BLAST.

À partir de la leçon

Week 1: Introduction to Sequence Alignment

<p>Welcome to class!</p><p>If you joined us in the previous course in this Specialization, then you became an expert at <em>assembling</em> genomes and sequencing antibiotics. The next natural question to ask is how to compare DNA and amino acid sequences. This question will motivate this week's discussion of <strong>sequence alignment</strong>, which is the first of two questions that we will ask in this class (the algorithmic methods used to answer them are shown in parentheses):</p><ol><li>How Do We Compare DNA Sequences? (<em>Dynamic Programming</em>)</li><li>Are There Fragile Regions in the Human Genome? (<em>Combinatorial Algorithms</em>)</li></ol><p>As in previous courses, each of these two chapters is accompanied by a Bioinformatics Cartoon created by talented artist Randall Christopher and serving as a chapter header in the Specialization's bestselling <a href="http://bioinformaticsalgorithms.com" target="_blank">print companion</a>. You can find the first chapter's cartoon at the bottom of this message. Why have taxis suddenly become free of charge in Manhattan? Where did Pavel get so much spare change? And how should you get dressed in the morning so that you aren't late to your job as a crime-stopping superhero? Answers to these questions, and many more, in this week's installment of the course.</p><p><img src="http://bioinformaticsalgorithms.com/images/cover/alignment_cropped.jpg" width="528"></p>